• Journal of Life Science
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• v.24 no.2
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• pp.148-153
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• 2014

The objective of this study was to elucidate the effect of light-emitting diode treatment on early growth and inorganic elements in leaf lettuce (Lactuca sativa L. 'Oak Leaf'). In changes to leaf morphology, shoot elongation and hypocotyl length showed poor growth under red light irradiation, while red+blue light irradiation induced shorter plant height and more leaves, resulting in increased fresh weight. With respect to Hunter's color and SPAD values, lettuce seedlings grown under red+ blue and fluorescent light irradiation had a higher $a^*$ value but showed no other changes to SPAD values. Interestingly, redness in relative chlorophyll content was 1.4 times higher under red+blue light irradiation. Inorganic element (N, Ca, Mg, and Fe) and ascorbic acid concentrations increased in lettuce plants grown under LED light irradiation compared to those of lettuce grown under fluorescent light, which showed a higher P content. In conclusion, red+blue light irradiation, which stimulates growth and higher nutrient uptake in leaf lettuce, could be employed in containers equipped with LEDs.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.33-35
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• 1977

The mean height growth of 1-1 Picea abies seedlings originated from two provenances, i.e., Hartz above 600m of altitude and Fichtel (Ober Pfalzer basin below 800m) were measured. The progeny from Fichtel out grew those of Harz. about 70% as fast as did tree from Hartz. The variance due to replications was greater in Fichtel than in Hartz. 1-0. Quercus borealis seedlings showed vigorous height growth. All these experiments were performed at Yangsan-gun Habuk-myeon, south-east place in Korea.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.66-73
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• 2004

Three species of Italian poplar (Populus euramericana), red pine (Pinus densiflora) and oriental oak (Quercus variabilis) were selected for this study. They were cut so that the distances between each of tips and roots for a pair of fingers were 0, 0.15, 0.30 and 0.45 mm. Poly vinyl acetate (PVAc) and resorcinol-phenol resin (RPR) were used for finger-jointing. Compressive test parallel to the grain was conducted for the finger-jointed specimens. The results were as follows: The efficiency of compressive Young's modulus of finger-jointed timber to solid wood indicated low values, whereas the efficiency of compressive strength indicated high values of more than 90% in all species, especially, it was found that those of red pine indicated markedly high values of more than 97%. The efficiency of compressive displacement of Italian poplar finger-jointed timber was 2 times higher than solid wood, and it was 1.2 and 1.3 times higher than solid woods in red pine and oriental oak, respectively. Also, it was found that 0, the distance between each tip and root for the fingers, indicated the highest efficiency of compressive strength performance in Italian poplar finger-jointed timber, and for red pine and oriental oak finger-jointed timbers, the distances of 0.15 and 0.30 were found to indicate the highest efficiency.

• Journal of Korea Foresty Energy
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• v.22 no.1
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• pp.44-48
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• 2003

Flexural properties were investigated on clear specimens made from small diameter thinned trees of pitch pine (Pinus rigida Mill.), Japanese red pine (Pinus densiflora Sieb. et Zucc), Japanese larch (Larix kaempferi Carr.), and sawtooth oak (Quercus acutissima Carr.). MOR and MOE values of small clear specimen were depended on the species. The highest density of sawtooth oak shows the highest values of MOR and MOE. However, the lowest density of Japanese larch shows the lowest values of MOR. It was also shown that flexural properties could be predicted by stress wave MOE, since the correlations between stress wave MOE and flexural properties were relatively good.

• Journal of the Korean Wood Science and Technology
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• v.9 no.3
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• pp.24-30
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• 1981

This experiment was carried out to determine the drying time from green to oven dry and estimate the moisture content of wood, such as red lauan (Shorea Spp.), Douglas fir (Pseudotsuga menziesii), Birch (Betula platyphylla), and oak (Quercus aliena), at various thickness, paralleled to fiber, of specimen for M.C. by oven dry method (100-105$^{\circ}C$). The results obtained are summarized as follows: 1. The drying time from green to oven dry decreases as the thickness of specimen for M.C. becomes to be thined, and that time at 10mm thickness are 14 hrs, for birch wood and 24 hrs, for oak wood. 2. The relative formulae between thickness (X) of specimen for M.C. and drying lime (Y) from 12% to oven dry are showed in Fig. 3. 3. The M.C. based on the weight of specimen for M.C. at t% can be obtained from the formula (2), and the drying time to 1% are shorter than that time to oven dry by approximately three times.

• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.478-485
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• 2015

The aim of this study is to analyze the combustion and thermal properties in order to establish baseline data for the fire safety evaluation of domestic timbers. The combustion properties such as heat release rate, total heat release, gas yield, and mass loss were analyzed by the method of cone calorimeter test and thermogravimetry (TGA). Thermal decomposition temperatures of the specimens by TGA were recorded as $359.83^{\circ}C$ for White pine, $359.80^{\circ}C$ for Red-Leaved Hornbeam, $363.14^{\circ}C$ for Carolina poplar, $358.59^{\circ}C$ for Konara oak, and $362.11^{\circ}C$ Sargent cherry. Red-Leaved Hornbeam showed the highest value of heat release rate, but, Carolina poplar wood showed the lowest value. In case of the total heat release, Red-Leaved Hornbeam wood showed the highest value and Carolina poplar wood showed the lowest one. The gas analysis results showed that Sargent cherry wood had the lowest value of 0.021, and Konara oak had the highest at 0.031 in the $CO/CO_2$. The minimum value of mass reduction was recorded as 87.57% for Sargent cherry, but, on the other hand, it was 95.03% for Konara oak. There was a correlation between the gas generation of CO and $CO_2$, and combustion behavior of woods. These results are expected to be usful for providing a fundamental guideline with the fire safety of wood use in interior applications.

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.93-100
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• 2008

For investigation of adsoption properties of cadmium elimination by wood charcoal, $25m{\ell}$ aqueous cadmium solutions in various concentrations were treated with 0.2 g wood charcoal of Red Oak (Quercus mongolica) for 280 minutes. Almost 100% of cadmium elimination ratio was obtained in the solutions with initial concentration of 20 and 40 ppm in the treatment, whereas they were 75 and 50% in those of 80 and 160 ppm. In the effect of treatment time, the highest amount of cadmium ions was eliminated during the first ten minutes in each solution so that the elimination ratio of each case was over 70% of the maximum elimination value. From the analysis of adsorptive cadmium adsorption mechanism using the Langmuir adsorption isotherm, it was suggested that cadmium ion molecules were adsorbed at the active sites on the charcoal particle in form of one layer. The Gibbs free energy of the adsorption process was calculated in negative value for each solution. This means the adsorption processes are spontaneous which do not require the extra input energy.

• Journal of the Korea Furniture Society
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• v.11 no.2
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• pp.79-84
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• 2000

It is well-known fact that dimensional stability of wood is greatly enhanced by acetylation of wood. This dimensional stability results from bulking of the reacted acetate within the cell wall, which reduces further swelling when the modified woods come into contact with water or water vapor. The purpose of this research was to determine the water absorption and dimensional stability of the acetylated solid wood in liquid water and in humidity tests. Beech and red oak were acetylated. Moisture and water absorption of acetylated wood were quite dependent on weight percent gain(WPG). Antiswelling efficiency(ASE) was quite dependent on WPG, but was not dependent on species.

• Journal of Species Research
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• v.3 no.1
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• pp.79-94
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• 2014

It was found that a total of 94 species of marine algae, 13 green algae, 24 brown algae, and 57 red algae, are living at the seashore of Oho-ri in this study. 739 voucher specimens for 94 species were made based on plants from March to September 2010 at the 3 islets, including Heukdo, Goraebawi, and Juckdo. Voucher specimens were catalogued and deposited in the herbarium of the National Institute of Biological Resources (KB) of Korea.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.753-763
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• 2015

To identify the overall status of vegetation in the nine ridges of the Jeongmaeks located in South Korea, the types of forest vegetation were analyzed with focus on the names of the plant communities that appeared in each Jeongmaek. The vegetation investigation data for the entire mountain ranges were used for quantitative analysis (TWINSPAN, DCA), thereby classifying the plant communities and understanding the structures and characteristics of the vegetation. Upon review of the ratios of the number of plant communities by each ridge of the Jeongmaeks, a relatively larger number of communities were found to be dominated by deciduous oak trees in the Honam and Nakdong Jeongmaek. In addition, the ratios of communities where deciduous oak trees and deciduous broad-leaved trees appeared were higher in the Hannam-geumbuk, Nakdong, Honam, Geumnam-honam, Geumnam and Geumbuk Jeongmaeks. On the other hand, Naknam, Hannam, and Hanbuk Jeongmaeks were shown to have the type of forest vegetation in which the ratio of artificial forests was high. According to the results of the quantitative analysis, eight communities were grouped as follows: Celtis sinensis-Mallotus japonicus, Deciduous oak, Pinus thunbergii-P. rigida, Quercus mongolica-P. densiflora, Q. mongolica-Q. variabilis, Q. mongolica-P. densiflora, Q. mongolica-broad-leaved deciduous and Q. mongolica-P. koraiensis communities. The typical forest vegetations in the Jeongmaeks were the Q. mongolica-dominant community, the P. densiflora-dominant community, and the deciduous oak-dominant community.